In order to effectively utilize heat emitted from factories, automobiles, electronic equipment, etc., a thermoelectric device that can convert heat energy to electric energy is being studied.
The material used for the thermoelectric device includes a thermoelectric material such as Mg—Si-based, Bi—Te-based, Pb—Te-based, Si—Ge-based and Fe—Si-based materials.
When a thermoelectric material contains a specific dopant, the performance of a thermoelectric device is enhanced. By containing a specific dopant element in the thermoelectric material, thermal conductivity is reduced, electrical conductivity is improved, and/or Seebeck coefficient is improved.
The Mg—Si-based thermoelectric material includes a thermoelectric material in which part of Si of magnesium silicide (Mg2Si) is replaced by Sn. Enhancing the thermoelectric performance is being studied by containing a dopant element in such a thermoelectric material.
For example, Patent Document 1 discloses a thermoelectric material having a composition of Mg2Si1-xLxMy (wherein L is either one of Sn and Ge, M is at least one member selected from Al, Ag, As, Cu, Sb, P, and B, x is from 0 to 0.5, and y is from 0 to 0.3).